Answer:
as far as the car can withstand
Explanation:
That would be like dropping your cell phone on to the ground by accident. The object (cell phone)'s gravitational potential energy would be converted to kinetic energy or energy in motion more precisely. This is just a hypothetical example though.
The elephant and the mouse having zero weight in a gravity free space will not bump into you at the same effect.
<u>Explanation:
</u>
When both are in a gravity free space, the weights are zero, as we know that the
But when they will acquire the speed of same magnitude, say v, their different masses will acquire different momentum, which will make the difference in effect while bumping.
And as we know 
Therefore, effect of impact by elephant will be more than that of mouse
. An elephant breaking into you will take you back faster than a mouse in space hits you.
Answer:
E. two times the original diameter
Explanation:
Resistance of a wire is:
R = ρ L/A
where ρ is the resistivity of the material, L is the length, and A is the cross-sectional area.
For a round wire with diameter d:
R = ρ L / (¼ π d²)
The two wires must have the same resistance, so:
ρ₁ L₁ / (¼ π d₁²) = ρ₂ L₂ / (¼ π d₂²)
The wires are made of the same material, so ρ₁ = ρ₂:
L₁ / (¼ π d₁²) = L₂ / (¼ π d₂²)
The new length is four times the old, so 4 L₁ = L₂:
L₁ / (¼ π d₁²) = 4 L₁ / (¼ π d₂²)
1 / (¼ π d₁²) = 4 / (¼ π d₂²)
Solving:
1 / (d₁²) = 4 / (d₂²)
(d₂²) / (d₁²) = 4
(d₂ / d₁)² = 4
d₂ / d₁ = 2
So the new wire must have a diameter twice as large as the old wire.
